In the process of using the harmonica, the most common way is blowing or suction, which will cause the vibration of the metal reed. The harmonica belongs to the wind instrument with free spring according to the music instrument classification. Its source length1.5 ~ 3.5cm reed instead of air column.The harmonica are mainly divided into the solo harmonica and ensemble harmonica during using. It will have different in the use. Its range will effectively be different according to its type and tonality. As a melody instrument, the harmonica can play two kinds of chords at least. High-level performer can blow out two relatively independent parts at the same time in while following the harmonica structure. Each of the holes in the blues harmonica is fitted with a pair of springs. The performer makes a note when exhaling and makes another note when inhaling. Each of the holes in the chromatic harmonica is fitted with a pair of springs. It can make 4 different notes with the button and breathing. The upper and lower holes of the tremolo harmonica have the same pitch. And it plays different notes by changing the hole suction .

The harmonica will have its high artistry in the process of playing. And the skillful performer can make a variety of effects by changing the articulation of the reeds and the pressure of the airflow. The harmonica is used for blues and country folk. And it is used in rock and roll.Now, with the advent of chromatic harmonica and the over blowing skill of the 10 holes harmonica, the harmonica can also play the classical music and some jazz music.